Hi --
--- In Ilya Goldberg <> wrote:
>
> I've been trying to do the same thing on a TS-7260, and ran into
the
> same issues. One maybe not-so-obvious issue is that if you call
> usleep() in user-space, you will go to sleep for a *minimum* of
10ms
> using the supplied kernel. Also, even if you don't call usleep(),
> the kernel can take the CPU away from your process, and will
probably
> not give it back until its next 10ms "time window".
>
> I think the only possible way of reading the ADC at its limit
(even
> in its slower 9ksps mode) requires writing a device driver.
There's
> simply no way to arrange the right usleep() behavior from user-
> space. Until I figure out how to compile device drivers, this
I haven't tried to maximize speed of the on-board adc, but there may
be an option for shorter sleeps in 2.4 kernels: nanosleep has some
special handling for shorter pauses, but you have to set SCHED_RR or
SCHED_FIFO for your process. See
http://tech.groups.yahoo.com/group/ts-7000/message/8262 for more
details.
But, I don't think you should expect much from the on-board adc. It
was designed as a touch screen interface, not a general purpose adc.
In fact, I believe the new manual cirrus just issued, covering all
of the ep93xx family, covers the touch screen registers but not the
adc use on the ep9302.
Regards, ........ Charlie
Yahoo! Groups Links
<*> To visit your group on the web, go to:
http://groups.yahoo.com/group/ts-7000/
<*> Your email settings:
Individual Email | Traditional
<*> To change settings online go to:
http://groups.yahoo.com/group/ts-7000/join
(Yahoo! ID required)
<*> To change settings via email:
<*> To unsubscribe from this group, send an email to:
<*> Your use of Yahoo! Groups is subject to:
http://docs.yahoo.com/info/terms/
|